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arXiv · 1111.2481

Non-Anomalous Discrete R-symmetry Decrees Three Generations

Jason L. Evans·Masahiro Ibe·John Kehayias·Tsutomu T. Yanagida
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Abstract

We show that more than two generations of quarks and leptons are required to have an anomaly free discrete R-symmetry larger than R-parity, provided that the supersymmetric Standard Model can be minimally embedded into a grand unified theory. This connects an explanation for the number of generations with seemingly unrelated problems like supersymmetry breaking, proton decay, the mu problem, and the cosmological constant through a discrete R-symmetry. We also show that three generations is uniquely required by a non-anomalous discrete R-symmetry in classes of grand unified theories such as the ones based on (semi-)simple gauge groups.

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Jason L. Evans, Masahiro Ibe, John Kehayias, Tsutomu T. Yanagida. 2012-11-06. Non-Anomalous Discrete R-symmetry Decrees Three Generations. https://doi.org/10.1103/physrevlett.109.181801

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